Apparatus for transferring solder bumps and method of using
US6003757A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 30, 1998 |
| Grant date | Dec 21, 1999 |
| Priority date | — |
| Expiry date | Apr 30, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05K2203/128
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
An apparatus and a method for transferring solder bumps from a solder mold to a solder-receiving substrate are disclosed. The apparatus includes a transfer fixture constructed by a base member, a lid member and a compressible member for holding a mold/substrate assembly therein. A plurality of compression pins are mounted through the lid member for supplying a uniform pressure on the mold/substrate assembly and for allowing lateral motion of the mold/substrate assembly relative to the transfer fixture due to a mismatch in the coefficients of thermal expansion. The compressible member is a cellulosic foam sheet which applies a uniform joining force across the entire surface of a wafer and assures abutting contact between the entire wafer and the mold surface. The foam sheet further assists in the lateral movement of the mold/substrate assembly relative to the base member of the transfer fixture.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.